I'm still a little amazed at how well my first "pointer", for lack of a better name, worked!  I was hoping to be able to indicate the sun's location to within about 10 seconds (time) and instead got lucky and obtained 6 second resolution.  It is able to comfortably indicate the sun's position in two perpendicular axis at once to within 1.5 min arc.  This is done with 18 inch [45,7cm] long, 1/4 inch [6.35mm] thick, and 2 inch [50.8mm] wide, plates.  When I designed it, I was hoping to be able to accurately detect .010 to .012 inch [.25-.30mm] of shadow, even with the 1/2 deg. penumbra.  Because of an unexpected bright reflection of the penumbra down the length, I am able to easily see the .008 inch [.20mm] necessary for the sensitivity observed.  Someday, with enough time and help to facilitate my technical presentation, I hope to finally present this very interesting "sundial with a pointer" in our Compendium.

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